Coordinated video-phone overlay on top of pc desktop display

ABSTRACT

Disclosed is a system and method for rendering a video from a video phone system to a monitor associated with a computing device such a PC. A chroma-key color is utilized to define a video window in the monitor and the video phone system will overlay video content in the window. A mouse pointer will continue to be visible even when it is in the video overlay location and continue to be able to manipulate and control content in the monitor, including the video layout.

FIELD OF THE INVENTION

The field of the invention relates generally to video calls and displayof video calls.

BACKGROUND OF THE INVENTION

A video phone may have video output ports, HDMI for example, which candrive an external monitors. This allows the end user to experience animmersive video conferencing which is not possible using small displaysthat are common with video phones. However, due to budget and/or limiteddesktop area, most users are unlikely to have a dedicated monitor forvideo calls. Alternatively, user may want to let the video phone sharethe PC monitor which is already available. Many monitors have two ormore video inputs so it may be possible to toggle between a full-screenPC and full screen video by using the monitor controls.

A video device may be enabled to accept a PC output and display ittogether with video. This may be accomplished by scaling the output.Additionally the video devices may be enabled to show full screen PC andfull screen video.

Video devices may be enabled to accept a PC output and display ittogether with video. This may be accomplished in two modes. A first modemay be a full screen video mode. A second mode may be a full screen PCwith a small overlay video in a fixed position.

A phone may be enabled to play audio and an accompanying PC may beenabled to receive an associated video stream. The PC would also decodethe video stream and show it on the monitor. The phone and the PC wouldwork in concert to present the corresponding video call in separatevideo and audio presentations.

SUMMARY OF THE INVENTION

An embodiment of the invention may therefore comprise a method forproviding content from an intermediate system to one of one or moremonitors associated with a computing device, wherein the computingdevice is operably linked to the intermediate system and theintermediate system is operably linked to one of the one or moremonitors, the method comprising by the intermediate system, sending amessage to a control application to open a window of a specific size ona desktop of the computing device, by the control application, opening awindow of the specific size on the desktop of the computing device, bythe control application, sending size, location on the desktop andchroma-key information of the opened window to the intermediate system,by the intermediate system, overlaying content on top of the location onthe desktop sent by the control application, and by the controlapplication, sending updated size and location information of the openedwindow to the intermediate system.

An embodiment of the invention may further comprise a system forrendering a video, the system comprising a computing device associatedwith one or more monitors, an intermediate system comprising a controlapplication and a control application, wherein the intermediate systemis enabled to send a message to the control application for the controlapplication to open a window of a specific size on a desktop of thecomputing device and overlay content on top of the location of thedesktop sent by the control application, and the control application isenabled to open a window of a specific size on the desktop of acomputing device, send size, location of the desktop and chroma-keyinformation of the opened window to the intermediate system and sendupdated size and location information of the opened window to theintermediate system.

An embodiment of the invention may further comprise a method fordisplaying content from an intermediate system to a monitor, the methodcomprising by the intermediate system, sending a request to a controlapplication via a network connection to open a window of a specific sizeon a desktop running in a virtual desktop environment on a virtualdesktop infrastructure server, by the control application, opening awindow on the desktop, by the control application, sending size,location and chroma-key information of the opened window to theintermediate system via the network connection, by the intermediatesystem, overlaying content on top of the location on the desktop sent bythe control application, and by the control application, sending updatedsize and location information of the opened window to the intermediatesystem via the network connection.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a system diagram of coordinated video-phone overlay systemconnectivity.

FIG. 2 is a diagram of a video overlay on a PC monitor.

FIG. 3 shows blank window opened by the control application before phoneoverlay and a mouse pointer covering part of the chroma key.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Video calls are more effective if participants to the video calls areprovided with a more total experience. In essence, this is accomplishedby providing a feeling to the participants that they are in the sameroom. There are a number of aspects that lend themselves to providingthis feeling. First, the video should be rendered on a display that isbig enough so that the torso and eyes of other participants are shown ina size that allows a user to comfortably view those other participants.The challenge of rendering a comfortable viewing of participants in amulti-party call increases due to the same monitor real estate now beingdivided in order to display the different participants concurrently.Second, a camera being used for the video call should be placed abovethe rendered video. While this may not be an absolute, for the camera tobe above the rendered video allows the level of a user's eyes tomaintain eye contact perception. Third, the video system should providea persistent high quality and low delay video channel. This last aspectis self-explanatory. A choppy video, poorly synced video or otherwiseunsuitable visual detracts from a quality video call experience.

Generally, video appliances, or video phones, are dedicated devices thatare optimized to provide persistent, high-quality and low delay video.In many cases a modem computer may support acceptable video callperformance. However, in many situations, the result may not be optimaldue to the fact that the computer is required to run other applicationsat the same time. This is especially true when the latest videocompression standards, such as H.264 high-profile or H.265 for example,are used. In many cases, a video phone system, or like appliance, hasthe advantage over a modem computer because it is a dedicated devicethat has application specific hardware which is optimized for videocompression and decompression (an ASIC, for example).

However, video-phones do not generally include large embedded displaysdue to the need to conserve space and the relatively high price of largedisplay panels. Moreover, the desire to make video-phones compact maylead to the video phone camera and display being located in a less thanoptimal position in the device. Several terms may be used throughout hisdescription to apply to systems intended to enable a use to engage in avideo conference using a personalized video phone type system. The termsare intended to apply to a video phone system which may present some ofthe size and clarity issues discussed. A video phone is a telephone witha video display capable of simultaneous video and audio forcommunication between people in real-time. Various terms, such as“personal video conferencing system”, or other term used herein areintended to refer to a video phone system as described.

A video phone enabled to have video output, such as HDMI, driving anexternal monitor do not enable a user to see the video call and anassociated PC desktop on the monitor simultaneously. It is understoodthat other types of connections are available. Other connections mayinclude DisplayPort, DVI (Digital Visual Interface), VGA (Video GraphicsArray), or other connection type such as Thunderbolt. A video deviceenabled to accept PC output and display it may allow a user to see videoand PC simultaneously but make it hard to read text from the PC after ascale down manipulation. This may be so because the PC uses TrueTypefonts which are rendered to match the current resolution. It isunderstood that TrueType font is an outline font standard that iscommonly used for fonts on both Mac OS and Microsoft Windows operatingsystems. TrueType font offers control over how fonts are displayed atvarious font sizes. Further, if the PC image includes text then scalingit down (so the video will fit) might make the font illegible. For videodevices which can accept PC output and display it together with video intwo modes, these devices are generally unable to show a large videowindow when the PC desktop is displayed. Further, a user may not have asufficient means to manipulate the video window to move it out of theway if it covers a toolbar or menu item that the user desires to access.Also, the video window may cover the mouse pointer if it happens to bebehind the window, causing a user to lose track of the mouse. It isunderstood that there are one or more devices that may overlay contentonto a semi-transparent window. However, in such a device, and solution,it does not allow a user to manipulate the window just as any otherwindow. The device, or solution, may allow a control application to takecontrol of a mouse and keyboard. The device, or solution, may thenrender a unique mouse pointer that can only interact with the GUI(Graphical User Interface) elements rendered by the desktop videodevice. As such, manipulation of the video and use of the cursor withinthe video window are severely restricted and may require specific actionby the user to switch control of the mouse and keyboard from onecontrolling device, the computer or the video device, to the other.

A phone that only plays the audio and the PC receives and plays anincoming video stream may be a soft-client application solution. Such asoft-client application requires that the PC have all video codecs.Also, an additional issue with a softclient is that the PC needs to havea CPU that is powerful enough and/or a PC with video compression anddecompression HW accelerators. Further video delay optimization isperformed on the PC (as those skilled in the art will understandsoft-client applications) and, if the PC's CPU is heavily loaded byother applications, video may accordingly lag or even drop frames. Asnoted, video and audio sync is difficult to assure due to the fact thatthey are rendered by different devices.

Embodiments of the invention are also applicable when a physical videodevice, such as a video phone, is a VDI client. A Virtual DesktopInfrastructure (VDI) is a desktop-centric service that hosts userdesktop environments on remote servers and/or blade PCs, which areaccessed over a network using a remote display protocol. A connectionbrokering service is used to connect users to their assigned desktopsessions. For users, this means they can access their desktop from anylocation, without being tied to a single client device. Since theresources are centralized, users moving between work locations can stillaccess the same desktop environment with their applications and data.For IT administrators, this means a more centralized, efficient clientenvironment that is easier to maintain and able to respond more quicklyto the changing needs of the user and business. Those skilled in the artwill understand uses of a VDI in embodiments of the invention.

A video phone may be enabled to share a large computer monitor which auser already has available. The computer monitor may be one associatedwith a PC or one that is associated with other monitors as discussed inthis description. A user may utilize the monitor, while using thecomputer, during a video call. Embodiments of the invention allow a userto conveniently see both the desktop user interface and functions of acomputer monitor and the video rendered by a video phone simultaneously.In some embodiments the user may be allowed to scale, move, hide andunhide a video rendered by a video phone on the PC monitor in a mannerconsistent with any other application. Those skilled in the art willunderstand the techniques available to manipulate applications and othervisualizations on a monitor. For instance, several keyboard or mousetechniques may be utilized. This provides usability of the embodimentsof the invention, especially when a video call appearance is sized toaccommodate most or a large portion of the monitor display area.

In an embodiment of the invention, methods and systems will have an HDMIinput that is connectable to a user's PC and an HDMI output that canconnect to a monitor. It is understood that other types of connectionsare available. Other connections may include DisplayPort, DVI (DigitalVisual Interface), VGA (Video Graphics Array), or other connection typesuch as Thunderbolt. Those skilled in the art will understandapplication of embodiments of the invention using these otherconnectivity types, as well as HDMI which is used here for purposes ofexample. As noted, the monitor may be associated with a PC or othercomputing device that provides a computing desktop. A computing deviceis a computer, such as a PC (Personal/Professional Computer) that allowsa computer's desktop environment to be run remotely on one system(usually a PC, but the concept applies equally to a server), while beingdisplayed on a separate client device. Those skilled in the art willunderstand applications of embodiments of the invention to a variety ofmonitor type functionalities. A video phone system is enabled with acontrol application that performs a variety of functions. The controlapplication (which may also be referred herein as a content applicationor a companion application) will be enabled to detect when the videophone system is connected to the PC and to which video display ports (ifthere are multiple ports). When a video call initiates through the videophone system, the video phone system will request that the controlapplication open a blank window on the associated PC monitor. Thecontrol application fills the window with a color (pre-defined ornegotiated) and sends the color code to the video phone along withwindow location and size. The video phone will overlay the renderedvideo call on top of the blank window that was created by the controlapp. The control application will fill the window with an appropriatecolor. The color may be pre-defined or negotiated. In either case, thecolor is a defined color, where the pre-defined aspect will result in adefined color or a negotiation will result in a defined color. The coloris used as a chroma-key by the system. Chroma key compositing, or chromakeying, is a special effects/post-production technique for compositing(layering) two images or video streams together based on color hues(chroma range). The technique has been used heavily in many fields toremove a background from the subject of a photo or video—particularlythe news casting, motion picture and videogame industries. A color rangein the top layer is made transparent, revealing another image behind. Inan embodiment of the invention, the content supplied by a device may beconsidered behind. The chroma keying technique is commonly used in videoproduction and post-production. This technique is also referred to ascolor keying, color-separation overlay (CSO), or by various terms forspecific color-related variants such as green screen, and bluescreen—chroma keying can be done with backgrounds of any color that areuniform and distinct.

Continuing with the embodiment of the invention, the control applicationwill update the video phone system about the window size and position inthe PC monitor desktop. The video phone system may have a hardware unitcan overlay content (like the video call) on-top of the incomingvideo-stream from the HDMI or the internal VDI client. In the currentembodiments, the incoming video stream is the PC desktop display. Thevideo phone system will place the video on the location specified by thecontrol application. The video phone system will also scale the videoappropriately to fit the window (but the PC display is not scaled andfont appearance is accordingly not affected). The video phone systemwill check the content of the multiple pixels inside the area specifiedby the control application to detect the numerical value of thechroma-key. This may be necessary in case the chroma-key was modified bythe PC display card due to color calibration, or otherwise. The videophone system will over lay the video content only for pixels where thecolor is equal to the numerical value of the chroma-key. Accordingly,the mouse pointer will be visible even when it is in the video overlaylocation. This is because the mouse pointer will cover the selectedchroma-key so that the video phone system will show it instead of thevideo in the appropriate location only. In the case where the display,or monitor, is without a PC, the video phone system may render the videoon the entire display.

The control application to the video phone system will send mouse clickcoordinates and key presses to the video phone system when the overlayvideo window is in focus. This allows the video phone system to renderuser-interface controls inside of the overlay window.

Embodiments of the invention allow a user to control the size andposition of video decoded and rendered by a phone using the PC keyboardand/or mouse. This type of operation of manipulating windows in adisplay is understood by those skilled in the art. Embodiments alsoallow a user to quickly move the video out of the way if it is in aninconvenient location. This type of operation of moving windows in adisplay is understood by those skilled in the art. A mouse pointer willnot be covered by the video which allows for full, or mostly full,screen windows to be utilized. Embodiments also allow a user to interactwith a user interface rendered by the video phone system withoutrequiring a change in the PC control application. Unlike a regulardevice control application which renders its own UI (User Interface),the embodiment described here allows the video phone to render its UIdirectly. Hence, it is possible to change the UI by changing only thephone's firmware (without changing the PC application). Essentially,seamless user interface integration of video rendered by a video phoneand personal computer desktop is provided by embodiments of theinvention.

FIG. 1 is a system diagram of coordinated video-phone overlay systemconnectivity. In the system 100, a video phone system 110 connects to aPC monitor 120. The PC monitor 120 may have an installed/embedded camera130. The video phone system 110 also connects to the PC 140. The videoconnections 190 of the video phone system 110 to the PC 140 and themonitor 110 may be HDMI connections. The PC is connected 180 to thenetwork 150 (showing a network connection and not an actual network—thenetwork is not shown) through the phone internal switch. The connection180 provides a communication channel between the computing device/PC 140and the video phone system 110. This connection 180 may be an Ethernettype connection. Those skilled in the art will understand otherconnectivity types and formats that enable video phone 110 tocommunicate with a network (not shown in FIG. 1) and a computingdevice/PC 140. The video connection 190 between the video phone 110 andthe computing device/PC 140 as well as the network connection 180between the video phone 110 and the computing device/PC 140 provides anoperable link between the video phone 110 and the computing device/PC140. Those skilled in the art will understand the exemplary nature ofthis embodiment. For instance, the video connection 190 and the networkconnection 180 may be combined into a connection that provides for bothcommunication between the video phone 110 and the computing device/PC140 and the sending in of video content from the computing device/PC 140to the video phone 110, with an opened blank window filled with aspecified chroma-key for example. The camera 130 installed with themonitor 120 is also connected to the phone 110. A keyboard 160 and mouse170 are used to provide input to the PC 140.

The video conference phone 110 HDMI 180 output allows it to render videoon a large monitor. However, as noted, a user may not desire to dedicatea whole monitor just for a video call. The video conference phone 110 isenabled to share the user's existing PC Monitor 120. The videoconference phone 110 is connected between the user's PC 140 and itsmonitor 120 so it is able to toggle between a video view, a PC view or acombined view on the user provided monitor.

FIG. 2 is a diagram of a video overlay on a PC monitor. A PC monitor 200is used to provide display of a video window 220 on the display area 210of the monitor. The video conference phone is enabled to overlay thevideo call window 220 on top of the user's PC desktop 210. For example,a typical 24 inch PC display has enough display area real estate to hosta meaningful size video and a PC application. FIG. 3 is a diagram of achroma-key overlay on a PC monitor. A control application will render ablank window (see FIG. 3) and render the video on top of it. This allowsfor a very lightweight, in size, resource requirements and complexity,control application. The video phone system will update the PC that anew video call has started and what its native resolution is. Thecontrol application will create a blank window and update the videophone system about its size and position. This update may be continuousor periodic. The video phone system will render the video on that exactposition. When the user moves, or resizes the window 220, the videophone system will update the video overlay size and position. Thisallows the user to move and resize the video window 220 to a preferredsize and position allowing use of the rest of the desktop. Those skilledin the art will understand rendering video windows in embodiments of theinvention. A PC application will verify that it renders the empty videowindow on the monitor that is connected to the video phone system.Further, in an embodiment of the invention the control application maynotify the video phone that the user wishes to open a window for use ina video call. In such an embodiment, the control application may have atray icon on the desktop (in windows for example) that allows the userto launch the application. It is understood that the tray icon may beotherwise enabled to allow for a user selection. Upon selection of theicon, the control application will open a window on the desktop andcommunicate with the video phone regarding the opened window and providethe same information regarding the window as if the video phone hadrequested that it me opened. In such an embodiment, the user is enabledto control when the video phone will utilize the desktop to providevideo content to a call.

FIG. 3 shows a blank window opened by the control application beforephone overlay and a mouse pointer covering part of the chroma key. A PCwill fill the blank window 320 with a pre-defined color and send thecolor code to the video phone system—along with the window size andlocation in the monitor desktop 310. The video phone system will treatthe received color as transparent and will render the video only inpixels where the PC color equals the color-key. When the PC mousepointer is over the video window, it covers the special color used. Itthereby prevents the video phone system from rendering video on top ofthe mouse pointer.

The image/video rendered by the video phone on top of the blank-windowcreated by the control application may, in addition to or instead of thevideo also user interface controls such as change layout, mute,participate, etc. As mentioned earlier, if the user clicks inside thewindow, the control application will send the click event position tothe video phone. An event may be created within a window by using themouse to click an icon, or other content, within the window or any othergenerally accepted manipulation of window data and content with a mouseas is understood by those skilled in the art. This allows the videophone to detect which of its user interface controls was selected by theuser and react accordingly. Hence, on the same monitors there can beuser interface elements rendered by the PC and user interface renderedby the video phones which are controlled in the same manner. Followingthe same rationale, when the control application blank window is ‘infocus’ it sends to the video phone all keyboard click events. This willallow the control application to send mouse click positions inside thevideo window to the video phone system. The video phone system is ableto detect when a user presses one of the controls.

Another important configuration for this invention is when the videophone is also a Virtual Desktop Infrastructure Client. In this mode, thePC display arrives to the video phone compressed though the data networkand not though a raw-video physical interface (like HDMI/DVI/DP/VGA). Inthis case the control application is running on the remote VDI serverswhich run the virtual PC for the user. In a way, this is moreinteresting than the regular configuration because, in many cases, VDIcan't support real-time requirements of video and audio calls.

Throughout this description, a method and system for combining videophone system generated content, which may include video, graphics anduser-interface elements, on top of a PC desktop in a way that allowsusers to manipulate and interact with the video phone system generatedcontent in a manner akin to how the user interacts with other PCapplications is presented. It is understood that the method and systemis applicable with a computing device such as the PC (Personalcomputer), discussed throughout this description as an example, as wellas a virtual PC running on VDI. FIG. 1 shows an embodiment of theinvention utilizing operable connections to a computing device/PC 140 toenable the sending of video to the video phone 110. While the PC and thevideo phone system are herein used as appropriate examples, it isunderstood by those skilled in the art that any type of computingdevice, whether a PC or virtual PC or other device capable of generatinggraphic and video content on a monitor, are perfectly suited to themethods and systems of the invention. Equally, the video phone system isused as an example for a use of the method and system of the inventionbut those skilled in the art will understand that any intermediateappliance or system capable of receiving or generating content tooverlay on a window generated from the PC, or otherwise, device. While aVDI environment is not specifically shown in FIG. 1, it is understood bythose skilled in the art how to utilize embodiments shown and discussedto provide video content to the video phone 110 through operable linksto either a physical computing device or a desktop rendered by a VDIclient. In accordance with embodiments of the invention which mayinclude and utilize a VDI environment, a virtual PC will run on VDI withthe video-phone system acting as a VDI client.

Further, a control application is referenced throughout this descriptionas providing functionality to the video phone system in relation to thecomputing device and the overlay of content on a window. The controlapplication may reside on the video phone system or on the PC andfunction as herein described. Embodiments of the invention include thecontrol application, as well as the other functionalities and hardwaregenerally associated with a video phone as is understood by thoseskilled in the art, regardless of where that control applicationresides. Those skilled in the art will understand usages of a controlapplication in any manner of settings.

The foregoing description of the invention has been presented forpurposes of illustration and description. It is not intended to beexhaustive or to limit the invention to the precise form disclosed, andother modifications and variations may be possible in light of the aboveteachings. The embodiments were chosen and described in order to bestexplain the principles of the invention and its practical application tothereby enable others skilled in the art to best utilize the inventionin various embodiments and various modifications as are suited to theparticular use contemplated. It is intended that the appended claims beconstrued to include other alternative embodiments of the inventionexcept insofar as limited by the prior art.

What is claimed is:
 1. A method for providing content from anintermediate system to one of one or more monitors associated with acomputing device, wherein the computing device is operably linked to theintermediate system and the intermediate system is operably linked toone of the one or more monitors, the method comprising: by the controlapplication, opening a window of the specific size on the desktop of thecomputing device, wherein the opened window is filled with a definedcolor; by the control application, sending size, location on the desktopand chroma-key information of the opened window to the intermediatesystem; by the intermediate system, overlaying content on top of thelocation on the desktop sent by the control application; and by thecontrol application, sending updated size and location information ofthe opened window to the intermediate system.
 2. The method of claim 1,wherein the computer device comprises at least one user interfacemechanism, the method further comprising: by the intermediate system,rendering at least one user interface element in the opened window; andby the control application, sending interface element events with eventposition data to the intermediate system resulting from an event createdby the at least one user interface mechanism.
 3. The method of claim 1,the method further comprising sending a chroma-key value from thecontrol application to the intermediate system, the chroma-key valuebeing associated with the defined color.
 4. The method of claim 3, themethod further comprising: by the intermediate application, checking thecontent of pixels inside the specified area of the opened window in aplurality of locations to detect a numerical value of a chroma-keyvalue; and by the intermediate system, compensating for chromaticalterations when detecting pixels filled by the control application withthe chroma-key.
 5. The method of claim 1, wherein the intermediatesystem is a video phone system and the content is video content.
 6. Themethod of claim 1, wherein the control application resides on saidcomputing device.
 7. The method of claim 1, wherein the method furthercomprises, by the intermediate system, sending a message to a controlapplication to open a window of a specific size on a desktop of thecomputing device.
 8. The method of claim 1, wherein the method furthercomprises, by the control application, notifying the intermediateapplication that a window is opened on the computing device.
 9. A systemfor rendering a video, the system comprising: a computing deviceassociated with one or more monitors; an intermediate system comprisinga control application; and a control application; wherein: theintermediate system is enabled to communicate with the controlapplication regarding opening a window of a specific size on a desktopof the computing device and overlay content on top of the location ofthe desktop sent by the control application; and the control applicationis enabled to open a window of a specific size on the desktop of acomputing device, the opened window being filled with a defined color,send size, location of the desktop and chroma-key information of theopened window to the intermediate system and send updated size andlocation information of the opened window to the intermediate system.10. The system of claim 9, wherein the computer device comprises atleast one user interface mechanism, wherein the intermediate system isfurther enabled to render user interface elements in the opened windowand to send interface element events with event position data to theintermediate system resulting from an event created by the at least oneuser interface.
 11. The system of claim 9, wherein the controlapplication is further enabled to check the content of pixels inside thespecified area as the opened window in a plurality of locations todetect a numerical value of a chroma-key value, the chroma-key valuebeing associated with the defined color, and wherein the intermediatesystem is further enabled to compensate for chromatic alterations. 12.The system of claim 9, wherein the intermediate system is a video phonesystem.
 13. The system of claim 12, wherein the content is videocontent.
 14. A method for displaying content from an intermediate systemto a monitor, wherein the intermediate system is a video phone embeddedwith a virtual desktop infrastructure client, the method comprising:sending a communication between the intermediate system and the controlapplication regarding opening a window of a specific size on a desktoprunning in a virtual desktop environment on a virtual desktopinfrastructure server; by the control application, opening a window onthe desktop, wherein the opened window is filled with a defined color;by the control application, sending size, location and chroma-keyinformation of the opened window to the intermediate system via thenetwork connection; by the intermediate system, overlaying content ontop of the location on the desktop sent by the control application; andby the control application, sending updated size and locationinformation of the opened window to the intermediate system via thenetwork connection.
 15. The method of claim 14, wherein at least oneuser interface mechanism is enabled to interface with the desktop, themethod further comprising: by the intermediate system, rendering atleast one user interface element in the opened window; and by thecontrol application, sending interface element events with eventposition data to the intermediate system resulting from an event createdby the at least one user interface mechanism.
 16. The method of claim14, the method further comprising sending a chroma-key value from thecontrol application to the intermediate system.
 17. The method of claim16, the method further comprising: by the intermediate application,checking the content of multiple pixels inside the specified area of theopened window to detect a numerical value of a chroma-key value, thechroma-key value being associated with the defined color; and by theintermediate system, compensating for chromatic alterations whendetecting pixels filled by the control application with the chroma-key.18. The method of claim 14, wherein the intermediate system is a videophone system and the content is video content.
 19. The method of claim18, wherein the process of sending a communication between theintermediate system and the control application comprises, by theintermediate device, sending a message to a control application to opena window of a specific size on a desktop of the computing device. 20.The method of claim 18, wherein the process of sending a communicationbetween the intermediate system and the control application comprises,by the control application, notifying the intermediate application thata window is opened on the computing device.